diff --git a/packages/interfaces/src/peer_exchange.ts b/packages/interfaces/src/peer_exchange.ts
index 9e713fcdb6..55d14012aa 100644
--- a/packages/interfaces/src/peer_exchange.ts
+++ b/packages/interfaces/src/peer_exchange.ts
@@ -3,12 +3,14 @@ import type { PeerStore } from "@libp2p/interface";
 import type { ConnectionManager } from "@libp2p/interface-internal";
 
 import { IEnr } from "./enr.js";
-import { IBaseProtocol } from "./protocols.js";
+import { IBaseProtocol, ProtocolResult } from "./protocols.js";
 
 export interface IPeerExchange extends IBaseProtocol {
-  query(params: PeerExchangeQueryParams): Promise<PeerInfo[] | undefined>;
+  query(params: PeerExchangeQueryParams): Promise<PeerExchangeResult>;
 }
 
+export type PeerExchangeResult = ProtocolResult<"peerInfos", PeerInfo[]>;
+
 export interface PeerExchangeQueryParams {
   numPeers: number;
   peerId: PeerId;
diff --git a/packages/peer-exchange/src/waku_peer_exchange.ts b/packages/peer-exchange/src/waku_peer_exchange.ts
index 9471b72271..babb6bf688 100644
--- a/packages/peer-exchange/src/waku_peer_exchange.ts
+++ b/packages/peer-exchange/src/waku_peer_exchange.ts
@@ -1,10 +1,11 @@
 import { BaseProtocol } from "@waku/core/lib/base_protocol";
 import { EnrDecoder } from "@waku/enr";
-import type {
+import {
   IPeerExchange,
   Libp2pComponents,
   PeerExchangeQueryParams,
-  PeerInfo,
+  PeerExchangeResult,
+  ProtocolError,
   PubsubTopic
 } from "@waku/interfaces";
 import { isDefined } from "@waku/utils";
@@ -34,18 +35,18 @@ export class WakuPeerExchange extends BaseProtocol implements IPeerExchange {
   /**
    * Make a peer exchange query to a peer
    */
-  async query(
-    params: PeerExchangeQueryParams
-  ): Promise<PeerInfo[] | undefined> {
+  async query(params: PeerExchangeQueryParams): Promise<PeerExchangeResult> {
     const { numPeers } = params;
-
     const rpcQuery = PeerExchangeRPC.createRequest({
       numPeers: BigInt(numPeers)
     });
 
     const peer = await this.peerStore.get(params.peerId);
     if (!peer) {
-      throw new Error(`Peer ${params.peerId.toString()} not found`);
+      return {
+        peerInfos: null,
+        error: ProtocolError.NO_PEER_AVAILABLE
+      };
     }
 
     const stream = await this.getStream(peer);
@@ -65,15 +66,17 @@ export class WakuPeerExchange extends BaseProtocol implements IPeerExchange {
       });
 
       const { response } = PeerExchangeRPC.decode(bytes);
-
       if (!response) {
         log.error(
           "PeerExchangeRPC message did not contains a `response` field"
         );
-        return;
+        return {
+          peerInfos: null,
+          error: ProtocolError.EMPTY_PAYLOAD
+        };
       }
 
-      return Promise.all(
+      const peerInfos = await Promise.all(
         response.peerInfos
           .map((peerInfo) => peerInfo.enr)
           .filter(isDefined)
@@ -81,9 +84,17 @@ export class WakuPeerExchange extends BaseProtocol implements IPeerExchange {
             return { ENR: await EnrDecoder.fromRLP(enr) };
           })
       );
+
+      return {
+        peerInfos,
+        error: null
+      };
     } catch (err) {
       log.error("Failed to decode push reply", err);
-      return;
+      return {
+        peerInfos: null,
+        error: ProtocolError.DECODE_FAILED
+      };
     }
   }
 }
diff --git a/packages/peer-exchange/src/waku_peer_exchange_discovery.ts b/packages/peer-exchange/src/waku_peer_exchange_discovery.ts
index dc49339823..bbf3ca6ff6 100644
--- a/packages/peer-exchange/src/waku_peer_exchange_discovery.ts
+++ b/packages/peer-exchange/src/waku_peer_exchange_discovery.ts
@@ -7,7 +7,12 @@ import type {
   PeerId,
   PeerInfo
 } from "@libp2p/interface";
-import { Libp2pComponents, PubsubTopic, Tags } from "@waku/interfaces";
+import {
+  Libp2pComponents,
+  PeerExchangeResult,
+  PubsubTopic,
+  Tags
+} from "@waku/interfaces";
 import { encodeRelayShard, Logger } from "@waku/utils";
 
 import { PeerExchangeCodec, WakuPeerExchange } from "./waku_peer_exchange.js";
@@ -160,15 +165,15 @@ export class PeerExchangeDiscovery
     }, queryInterval * currentAttempt);
   };
 
-  private async query(peerId: PeerId): Promise<void> {
-    const peerInfos = await this.peerExchange.query({
+  private async query(peerId: PeerId): Promise<PeerExchangeResult> {
+    const { error, peerInfos } = await this.peerExchange.query({
       numPeers: DEFAULT_PEER_EXCHANGE_REQUEST_NODES,
       peerId
     });
 
-    if (!peerInfos) {
-      log.error("Peer exchange query failed, no peer info returned");
-      return;
+    if (error) {
+      log.error("Peer exchange query failed", error);
+      return { error, peerInfos: null };
     }
 
     for (const _peerInfo of peerInfos) {
@@ -214,6 +219,8 @@ export class PeerExchangeDiscovery
         })
       );
     }
+
+    return { error: null, peerInfos };
   }
 
   private abortQueriesForPeer(peerIdStr: string): void {
diff --git a/packages/relay/src/index.ts b/packages/relay/src/index.ts
index a5f6f241f7..3b00f57f84 100644
--- a/packages/relay/src/index.ts
+++ b/packages/relay/src/index.ts
@@ -20,8 +20,8 @@ import {
   IRelay,
   Libp2p,
   ProtocolCreateOptions,
+  ProtocolError,
   PubsubTopic,
-  SendError,
   SendResult
 } from "@waku/interfaces";
 import { isWireSizeUnderCap, toAsyncIterator } from "@waku/utils";
@@ -107,7 +107,7 @@ class Relay implements IRelay {
       log.error("Failed to send waku relay: topic not configured");
       return {
         recipients,
-        errors: [SendError.TOPIC_NOT_CONFIGURED]
+        errors: [ProtocolError.TOPIC_NOT_CONFIGURED]
       };
     }
 
@@ -116,7 +116,7 @@ class Relay implements IRelay {
       log.error("Failed to encode message, aborting publish");
       return {
         recipients,
-        errors: [SendError.ENCODE_FAILED]
+        errors: [ProtocolError.ENCODE_FAILED]
       };
     }
 
@@ -124,7 +124,7 @@ class Relay implements IRelay {
       log.error("Failed to send waku relay: message is bigger that 1MB");
       return {
         recipients,
-        errors: [SendError.SIZE_TOO_BIG]
+        errors: [ProtocolError.SIZE_TOO_BIG]
       };
     }